Ethernets are high speed networks, either electrical or optical, which are used widely to transmit high volumes of data between different nodes on a network. Such networks are getting faster all the time, as end users become more and more data hungry for streaming media content. At the time of filing this application 10 Gbit/s (gigabits per second or Gbps) Ethernet is the fastest of the Ethernet standards and is set out in standard IEEE 802.3-2005. The 10 Gbit/s Ethernet standard employs a system of duplex links connected by switches, each link comprising a transponder/transceiver which functions as a transmitter and a receiver of 10 Gbit/s optical signals.
There is now a proposal under open discussion to increase the speed, with speed of 100 Gbit/s of more. An Ethernet standard for 100 Gbit/s is presently under early development by the IEEE. The objective is to transmit data at the higher rate of 100 Gbit/s across a network with noise error levels below an acceptable level.
Currently there are no commercially available transceivers (by which we mean a combined transmitter and optionally a receiver) for 100 Gbit/s or higher. Laboratory experiments have centred on the use of Electrical and Optical time domain multiplexing (ETDM and OTDM) combined with wavelength division multiplexing to achieve the higher bit rate. These techniques use multiple wavelengths transmitted simultaneously. More wavelengths allow more signals or channels of data to be passed down a fibre at the same time. Unfortunately there are no currently available components for the optical modulator for such a scheme, in particular for the use with different wavelengths, meaning that the cost of implementing such a scheme will be very high as new devices need to be designed and placed into production.